Multiply, reduce to lowest terms, and write as a mixed number: $ 3\dfrac{3}{4} \times 2\dfrac{3}{5} $
$ = \dfrac{15}{4} \times \dfrac{13}{5}$ $ = \dfrac{15 \times 13}{4 \times 5}$ $ = \dfrac{195}{20}$ $ = \dfrac{39}{4}$ $ = 9 \dfrac{3}{4}$